A number of thermal developments are currently in execution in Oman. Two of these are located in South Oman and contain an exceptionally thick column (200m+) of heavy oil (200 to 400,000 cp) in Cambrian reservoirs at a depth of 1050 m below surface, underlain by a moderately strong aquifer. One of the fields has been in production for 20 years, the main production mechanisms are pressure depletion and natural ingress of aquifer water, while the other field has only produced a small amount by cyclic steam stimulation (CSS) trials due to the high viscosity of its heavy oil. For the next phase of development a vertical well pattern re-development is planned which will increase the ultimate recovery significantly, through a combination of cold production, CSS and steam flooding.

The thickness of these reservoirs is unusually large for steamflooding and this poses both opportunities and challenges. There are no direct analogues and the industry practices of managing a steamflood in this specific setting is yet to be verified. Phase I deliberately addresses only the upper parts of the reservoirs while significant volumes are still to be matured in a future Phase II development. Following some higher level screening work of recovery mechanisms, the realistic development options for Phase II are innovative application of further steam flooding. Subsurface uncertainties are actively managed by different means; among them are the steam injection trials and steam pilot. The full field developments planned to start-up with Phase I in 2012 followed by Phase II in 2017.

The paper will provide an overview of the proposed Phase II thermal development and specifically the innovative way development challenges are addressed. The integrated modeling work that yielded a better design of well completion strategies will be discussed. Additional topics addressed include minimising additional gas requirements through application of co-generation of electricity and steam (COGEN), water management and overall integrated project management.

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